• Title/Summary/Keyword: Space classification

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RECURRENT PATTERNS IN DST TIME SERIES

  • Kim, Hee-Jeong;Lee, Dae-Young;Choe, Won-Gyu
    • Journal of Astronomy and Space Sciences
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    • v.20 no.2
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    • pp.101-108
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    • 2003
  • This study reports one approach for the classification of magnetic storms into recurrent patterns. A storm event is defined as a local minimum of Dst index. The analysis of Dst index for the period of year 1957 through year 2000 has demonstrated that a large portion of the storm events can be classified into a set of recurrent patterns. In our approach, the classification is performed by seeking a categorization that minimizes thermodynamic free energy which is defined as the sum of classification errors and entropy. The error is calculated as the squared sum of the value differences between events. The classification depends on the noise parameter T that represents the strength of the intrinsic error in the observation and classification process. The classification results would be applicable in space weather forecasting.

Label Embedding for Improving Classification Accuracy UsingAutoEncoderwithSkip-Connections (다중 레이블 분류의 정확도 향상을 위한 스킵 연결 오토인코더 기반 레이블 임베딩 방법론)

  • Kim, Museong;Kim, Namgyu
    • Journal of Intelligence and Information Systems
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    • v.27 no.3
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    • pp.175-197
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    • 2021
  • Recently, with the development of deep learning technology, research on unstructured data analysis is being actively conducted, and it is showing remarkable results in various fields such as classification, summary, and generation. Among various text analysis fields, text classification is the most widely used technology in academia and industry. Text classification includes binary class classification with one label among two classes, multi-class classification with one label among several classes, and multi-label classification with multiple labels among several classes. In particular, multi-label classification requires a different training method from binary class classification and multi-class classification because of the characteristic of having multiple labels. In addition, since the number of labels to be predicted increases as the number of labels and classes increases, there is a limitation in that performance improvement is difficult due to an increase in prediction difficulty. To overcome these limitations, (i) compressing the initially given high-dimensional label space into a low-dimensional latent label space, (ii) after performing training to predict the compressed label, (iii) restoring the predicted label to the high-dimensional original label space, research on label embedding is being actively conducted. Typical label embedding techniques include Principal Label Space Transformation (PLST), Multi-Label Classification via Boolean Matrix Decomposition (MLC-BMaD), and Bayesian Multi-Label Compressed Sensing (BML-CS). However, since these techniques consider only the linear relationship between labels or compress the labels by random transformation, it is difficult to understand the non-linear relationship between labels, so there is a limitation in that it is not possible to create a latent label space sufficiently containing the information of the original label. Recently, there have been increasing attempts to improve performance by applying deep learning technology to label embedding. Label embedding using an autoencoder, a deep learning model that is effective for data compression and restoration, is representative. However, the traditional autoencoder-based label embedding has a limitation in that a large amount of information loss occurs when compressing a high-dimensional label space having a myriad of classes into a low-dimensional latent label space. This can be found in the gradient loss problem that occurs in the backpropagation process of learning. To solve this problem, skip connection was devised, and by adding the input of the layer to the output to prevent gradient loss during backpropagation, efficient learning is possible even when the layer is deep. Skip connection is mainly used for image feature extraction in convolutional neural networks, but studies using skip connection in autoencoder or label embedding process are still lacking. Therefore, in this study, we propose an autoencoder-based label embedding methodology in which skip connections are added to each of the encoder and decoder to form a low-dimensional latent label space that reflects the information of the high-dimensional label space well. In addition, the proposed methodology was applied to actual paper keywords to derive the high-dimensional keyword label space and the low-dimensional latent label space. Using this, we conducted an experiment to predict the compressed keyword vector existing in the latent label space from the paper abstract and to evaluate the multi-label classification by restoring the predicted keyword vector back to the original label space. As a result, the accuracy, precision, recall, and F1 score used as performance indicators showed far superior performance in multi-label classification based on the proposed methodology compared to traditional multi-label classification methods. This can be seen that the low-dimensional latent label space derived through the proposed methodology well reflected the information of the high-dimensional label space, which ultimately led to the improvement of the performance of the multi-label classification itself. In addition, the utility of the proposed methodology was identified by comparing the performance of the proposed methodology according to the domain characteristics and the number of dimensions of the latent label space.

Type Classification of Contemporary Hanok -Focusing on Architects' Designs since 2000- (현대한옥의 유형 분류 -2000년 이후 건축가의 디자인을 중심으로-)

  • Lee, Yong-Hee;Kim, Hyon-Sob
    • Journal of architectural history
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    • v.25 no.5
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    • pp.51-62
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    • 2016
  • Since the recent Hanok boom in Korea, Contemporary Hanok has been evolving in terms of structure, space, form, etc. To get a comprehensive understanding of the diversified Contemporary Hanok, this paper aims at its type classification by analyzing architects' designs since 2000. The criteria for the classification are two: (1) renovation [Re] or new construction [New]; and (2) degree of Contemporary Hanok's deviation from the traditional Hanok's standard - maintaining the traditional form [Main]; changing space within the traditional form [Space]; changing the traditional frame [Frame]; and juxtaposing the traditional and the modern [Combi]. From the two criteria, this paper deduced eight types of Contemporary Hanok, named respectively: Re-Main, New-Main, Re-Space, New-Space, Re-Frame, New-Frame, Re-Combi, and New-Combi, and studied their cases. It can be argued that various aspects of Contemporary Hanok and their critical meanings were well-investigated through this type classification and case-studies.

Analysis of Classification Accuracy for Multiclass Problems (다중 클래스 분포 문제에 대한 분류 정확도 분석)

  • 최의선;이철희
    • Proceedings of the IEEK Conference
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    • 2000.06d
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    • pp.190-193
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    • 2000
  • In this paper, we investigate the distribution of classification accuracies of multiclass problems in the feature space and analyze performances of the conventional feature extraction algorithms. In order to find the distribution of classification accuracies, we sample the feature space and compute the classification accuracy corresponding to each sampling point. Experimental results showed that there exist much better feature sets that the conventional feature extraction algorithms fail to find. In addition, the distribution of classification accuracies is useful for developing and evaluating the feature extraction algorithm.

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Photometric and Spectroscopic Morphology Classifications Using SDSS DR7 : Virgo Cluster

  • Kim, Suk;Rey, Soo-Chang;Sung, Eon-Chang;Lisker, Thorsten;Jerjen, Helmut;Lee, Young-Dae;Chung, Ji-Won;Pak, Min-A;Yi, Won-Hyeong
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.69.1-69.1
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    • 2011
  • While the Virgo Cluster Catalog (VCC) is well established catalog from deep photographic plate survey, with available survey data recently released (e.g., SDSS), it can be further updated concerning the membership and morphology of galaxies. While membership and morphology of galaxies included in the VCC are based on the single band imaging data, thanks to the multi-color imaging and spectroscopic observations of SDSS, we are able to revise the membership and morphology of sample galaxies in the fields of the Virgo cluster. We present a new catalog of galaxies in the Virgo cluster using SDSS DR7 data, the extended Virgo cluster catalog. Using SDSS imaging and spectroscopic data, we introduce two kinds of galaxy classifications which are complementary each other. In addition to traditional morphological classification by visual inspection of the images ("Primary Classification"), we also attempt to classify galaxies with the spectroscopic features ("Secondary Classification"). The primary classification is basically based on the scheme of galaxy morphological classification of VCC. The secondary classification relies on the SED shape and presence of emission/absorption lines returned from SDSS. Our morphological classifications allow to study the evolution and associated star formation histories of galaxies in the Virgo cluster.

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A Study on Community Classification and Property Analysis for Space Planning of Elementary School -Focusing on the Seoul and Gyeonggi Province- (초등학교 공간계획을 위한 지역유형분류 및 특성분석 -서울·경기 지역을 중심으로-)

  • Lee, Sang Min
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.3 no.2
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    • pp.21-37
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    • 2003
  • This study has the purpose for analysis of each region's property in order to plan a elementary school's space according to community property. For this analysis. we used classification method through classification analysis. classification analysis is one of the useful statistical analysis methode for determining each region's policy through classifying regions which have a similar property. On this study, Seoul and Kyongkido is classified by 4 groups and each group has a different community property. Such a analysis is thought of helping establishing the objective. reasonable space-plan through comparative analysis between subjective claim and objective state indicator of each region.

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SPACE-LIKE SURFACES WITH 1-TYPE GENERALIZED GAUSS MAP

  • Choi, Soon-Meen;Ki, U-Hang;Suh, Young-Jin
    • Journal of the Korean Mathematical Society
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    • v.35 no.2
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    • pp.315-330
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    • 1998
  • Chen and Piccinni [7] have classified all compact surfaces in a Euclidean space $R^{2+p}$ with 1-type generalized Gauss map. Being motivated by this result, the purpose of this paper is to consider the Lorentz version of the classification theorem and to obtain a complete classification of space-like surfaces in indefinite Euclidean space $R_{p}$ $^{2+p}$ with 1-type generalized Gauss map.p.

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A Study on the Pattern of Domestic Literature Museum and the Space.Form Composition Characteristic - Focused on Gyeongsang-do region - (국내 문학관 건축의 유형과 공간.형태구성 특징에 관한 연구 - 경상도 지역을 중심으로 -)

  • Jang, Hoon-Ick
    • Journal of The Korean Digital Architecture Interior Association
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    • v.11 no.3
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    • pp.69-77
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    • 2011
  • This study considered the characteristic through the present state of domestic literature museum and grouping by type to help the understanding for domestic literature museum. And conducted a case study on Gyeongsang-do region literature museum to grasp the space form composition characteristic of literature museum. The result gained through these studies is as follows. First, grouping domestic literature museum by type, we can conduct the classification founded on location character, an exhibition writer, and the main body of erection and maintenance management. Second, the classification founded on location character of literature museum is able to be divided into the type of the house of writer's birth, a literary work, writing, and etc. Third, the classification founded on the number of exhibition writers can be divided into the type of independence, an individual pavilion, and integration. Fourthly, the classification founded on the main body of erection and management can be divided into the case in which a local self-governing body is wholly in charge of erection and management, a local government is in charge of erection but entrusts management to a corporate body, etc., a corporate body is in charge of erection and management, and a private person is in charge of erection and management. Fifthly, speaking of the characteristic by type of the Gyeongsang-do region literature museum, the classification founded on location has the type of the house of writer's birth the most, the classification founded on the number of exhibition writers has the type of independence the most, and the classification founded on the main body of erection and management has the most the type in which a local self-governing body is in charge of erection and management. Also, for the characteristic by space form, the case which expresses the character of Korean traditional architecture by form is many the most, and there are pieces of work to pursue shape beauty through the articulation of mass or molding manipulation and the change by space form through the proper combination of concreteness and abstraction as well.

Subtype classification of Human Breast Cancer via Kernel methods and Pattern Analysis of Clinical Outcome over the feature space (Kernel Methods를 이용한 Human Breast Cancer의 subtype의 분류 및 Feature space에서 Clinical Outcome의 pattern 분석)

  • Kim, Hey-Jin;Park, Seungjin;Bang, Sung-Uang
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.04c
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    • pp.175-177
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    • 2003
  • This paper addresses a problem of classifying human breast cancer into its subtypes. A main ingredient in our approach is kernel machines such as support vector machine (SVM). kernel principal component analysis (KPCA). and kernel partial least squares (KPLS). In the task of breast cancer classification, we employ both SVM and KPLS and compare their results. In addition to this classification. we also analyze the patterns of clinical outcomes in the feature space. In order to visualize the clinical outcomes in low-dimensional space, both KPCA and KPLS are used. It turns out that these methods are useful to identify correlations between clinical outcomes and the nonlinearly protected expression profiles in low-dimensional feature space.

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Solar Cell Classification using Gaussian Mixture Models (가우시안 혼합모델을 이용한 솔라셀 색상분류)

  • Ko, Jin-Seok;Rheem, Jae-Yeol
    • Journal of the Semiconductor & Display Technology
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    • v.10 no.2
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    • pp.1-5
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    • 2011
  • In recent years, worldwide production of solar wafers increased rapidly. Therefore, the solar wafer technology in the developed countries already has become an industry, and related industries such as solar wafer manufacturing equipment have developed rapidly. In this paper we propose the color classification method of the polycrystalline solar wafer that needed in manufacturing equipment. The solar wafer produced in the manufacturing process does not have a uniform color. Therefore, the solar wafer panels made with insensitive color uniformity will fall off the aesthetics. Gaussian mixture models (GMM) are among the most statistically mature methods for clustering and we use the Gaussian mixture models for the classification of the polycrystalline solar wafers. In addition, we compare the performance of the color feature vector from various color space for color classification. Experimental results show that the feature vector from YCbCr color space has the most efficient performance and the correct classification rate is 97.4%.